反应详情

A mixture of 29 (85 mg, 0.14 mmol) and CDI (47 mg, 0.29 mmol) in dry THF (7 mL) is heated at reflux for 2 h under nitrogen. LCMS analysis shows one peak of the intermediate (RT=5.37). The reaction mixture is cooled to room temperature and cyclopropylsulfonamide (52 mg, 0.43 mmol) is added. Then, DBU (50 μL, 0.33 mmol) is added and the reaction mixture is stirred at room temperature for 1 h, and then heated at 55° C. for 24 h. Solvent is evaporated, and the residue partitioned between AcOEt and acidic water (pH=3). The crude material is purified by column chromatography (AcOEt/CH2Cl2/Petroleum ether, 1:1:1). The residue is crystallized in Et2O, filtered to give the target compound contaminated with the cyclopropyl-sulfonamide. This material is triturated in 3 ml of water, filtered, washed with water and dried overnight in the high vacuum pump to give the target compound 30 as a white powder: m/z=708 (M+H)+.

1. temperatureis heated
2. temperatureat reflux for 2 h under nitrogen
3. customone peak of the intermediate (RT=5.37)
4. temperatureheated at 55° C. for 24 h
5. customSolvent is evaporated
6. customthe residue partitioned between AcOEt and acidic water (pH=3)
7. customThe crude material is purified by column chromatography (AcOEt/CH2Cl2/Petroleum ether, 1:1:1)
8. customThe residue is crystallized in Et2O
9. filtrationfiltered
10. customto give the target compound
11. customThis material is triturated in 3 ml of water
12. filtrationfiltered
13. washwashed with water
14. customdried overnight in the high vacuum pump